Tobacco smoke filter



1968 B. SOKOLOFF 3,407,821

TOBACCO SMOKE FILTER Filed March 30, 1967 INVENTOR. BORlS SOKOLOFF ATTORNEY United States Patent 3,407,821 TOBACCO SMOKE FILTER Boris Sokoloif, 825 Vistabula St., Lakeland, Fla. 33801 Filed Mar. 30, 1967, Ser. No. 627,112 3 Claims. (Cl. 131-265) ABSTRACT OF THE DISCLOSURE Citrus wastes from the juice industry, which include internal fruit pulp and the skins of oranges, lemons limes, tangerines, grapefruits, and any hybrid combinations of these, are processed by means of acid treatment and enzymatic decomposition to form a finely divided fibrous pulp. This pulp is then separated from the aqueous medlum to form a dry pulp in which the chemical properties of porosity are developed to a degree such that the material, either in the form of granules, or a fine powder, incorporated in filter paper is suitable for use as a medium through which tobacco smoke can be filtered.

The invention This invention relates to a smoke filter capable of removing tars from smoke and it is directly related to the preparation of a filter suitable for use in connection with tobacco and tobacco products which are smoked, particularly cigarettes. The specific aspect of the invention s the provision of the filter and filter substance in form suitable for incorporation into a cigarette as a filter tip.

Detailed description of the invention In accordance with this invention, citrus pulp, and by this I mean the entire mass of material obtained from citrus fruit after the extraction of juice, whether the pulp be in a pure dry form, or in a combination with citrus molasses, or other material, is utilizable as a basis for making a cigarette filter.

The invention may be understood by reference to the drawings in which FIGURE 1 is a section representing a filter of a cigarette filled with the material corresponding to this invention;

FIGURE 2 is a section through a cigarette butt filter formed of filter paper in accordance with the favored use of the product of this invention.

Citrus pulp contains certain ingredients which must be taken into account in processing it for use as a cigarette filter. Among the ingredients in the pulp are a small amount of protein, pectin, some flavenoids, some sugar and traces of citrus polysaccharides. These are accompanied by a proportion of cellulosic material. As citrus pulp is known and sold on the market, it is a crude yellow ish material which on inspection shows more or less large pieces of citrus fruit peel in the pulp. It is generally a Waste product from extraction of orange juice, from oranges alone, or from grapefruit or from tangerines alone. However, as a rule, the pulp as known to the market will include pulp from the orange and grapefruit.

In the process of preparing the final product from the pulp useful for filter purposes, my first step is to place the pulp as obtained in its crude form in distilled water using about a weight of water approximately equal to the weight of the pulp or roughly equal volumes of Water and pulp. To this, I add lactic acid, e.g. 95% aqueous solution in an amount suflicient to make the total concentration of lactic acid in the liquid medium 5% on a volume basis. Another acid, such as citric acid, tartaric, acetic, propionic, or other mild soluble organic acid might be used, but I have found that lactic acid gives best end results.

The acidified water suspension of the pulp is allowed to stand at ambient room temperature, namely, about 20- 30 C., for a period of 24 hours after whichit is filtered and the water insoluble material placed in warm, distilled Water at a temperature of about 3045 C., so that the Water content is about 55-60% by Weight. At this stage, it is important to evaluate the pH of the mixture and to keep it between 5.5 and 6.3. If the pH drifts above about 6.3, lactic acid should be added. At this stage, the enzyme papaine is added in the proportion of 0.001% by volume and the material is thus left in a temperature controlled condition at about 3640 C. for 2436 hours. Thereafter, another enzyme pectinesterase is added in the amount of 0.0002% by volume and the material is left under temperature controlled condition for 24-36 hours again, at a temperature in the range of 32-42 C. There is more temperature latitude in this second stage of the enzymatic treatment of the pulp than there is in the first, but the optimum level of activity seems to be at about 3840 C.

Upon completion of the enzymatic activity, after 20-36 hours, the material is filtered under pressure, dried and extracted with ethyl alcohol, 4565% concentration, filtered and dried. Higher concentrations may be used, but inasmuch as they are no more efiective than the 60% preferred, there is no need for so doing. Other alcohols, such as methanol, propyl, isopropyl, may be used. Following the extraction with alcohol, the material is filtered and dried. The material at this stage Will still appear to be in a relatively crude form with pieces of the pulp still showmg.

The chemical treatment of the pulp to reduce it to a manipulatable form is thus outlined in this step of the procedure.

In other words, at this stage of preparation the function of the acid is to regulate a fermentation while the pulp is being hydrolyzed and having the water soluble components thereof extracted, it is also to induce a minor degree of1 hydrolysis among hydrolyzable components of the pn p.

The enzyme treatment with papaine is typical. Other enzymes useful for the purpose would be, pepsin, protease, pectinesterase, etc., and they are used in essentially the same proportion. The purpose of the enzyme is to split protein. Pectinesterase splits pectin to produce methanol and pectate. Accordingly, in View of this fact, any of the enzymes which would be suitable for this biological reaction can be used. This partial hydrolysis is carried through for this purpose, i.e., to render the pulp essentially protein free and pectin free. The products of the hydrolysis remain in the pulp.

The alcohol extraction is preferably done with ethyl alcohol at a concentration of 30-60 or 70%. I have found that the 60% alcohol is essentially a preferred level because the concentration is a modest rate of consumption. It is quite effective for the solvent purpose and ethyl alcohol is relatively non-toxic. While methyl alcohol can be used, and it is to be expected that residual amounts of methyl alcohol, in the pulp product would be trivial, it is perhaps best to avoid it even though it is perfectly useful in the process. Also, other alcohols such as propyl and isopropyl can be used, but offer no advantage over ethyl alcohol.

After isolation of the crude pulp following the enzyme treatment, the crude material is convertible to the tar absorbing form of which I have two useful embodiments.

For preparation of the first of these forms of tar absorbing material, I employ pulverizing machinery having a screen of about 2 millimeters mesh size. After forcing the pulp through this mesh to obtain a relatively uniform granulated material dispersed in the fibrous pulp, I obtain a uniform granulated material, wash it for two hours with 60% ethyl alcohol. Here also, while methyl alcohol is useful, I prefer the ethyl.

To prepare the pulp for use in a cigarette filter paper, a very fine mesh is used. The material is of about a half millimeter screen and the pulp obtained is in the form of a very fine powder. This powder too is washed with 60% ethyl alcohol, filtered and dried. The powder in this form can be incorporated into filter paper to the extent of 75% of the material in the finished paper.

Having prepared the fine pulp, it can be used as such in a cigarette filter or it can be incorporated into a filter paper. In the latter case, the fine pulp is dispersed in the aqueous suspension of cellulose pulp for forming the filter paper sheet to the extent of 25-85% of the weight of solid material in the slurry being used to form the sheet and, thereupon, the material is formed into sheets with the random distribution or, rather, the uniform-random distribution of the pulp particles throughout the sheet. When the sheet is formed and dried, it can be cut and rolled to form the cigarette filter in conventional fashion.

In the drawings, in FIGURE 1, represents a cigarette consisting of paper tube 11 and butt tube 12 which may or may not be cork tipped. It is packed with tobacco 13 and the butt 12 is plugged with a filter-retaining material like cotton 14, followed by citrus granules 15, followed by another retainer 16. The precise manner of retaining the granular filter material in place is up to the manufacturer and the advantages of any particular method are for him to determine.

When the pulp is incorporated into a filter paper, generally a loosely matted cellulosic paper which is coiled randomly to form a filter suitable for inclusion in the tip, the construction will be like that shown in FIGURE 2, where represents the cigarette with paper tube 21 and end tube 22. The paper is filled with tobacco 23 and butt end is packed with the coiled filter paper 24. The coiled paper defines a large number of passages through its foraminous structure. The random-uniform distribution of citrus particles on the paper establishes the efficacy of the filter.

Test results Tests conducted, both with the granulated material as a granular material packed in a tube simulating a cigarette filter and the filter paper on absorbed tar and nicotine following the method prescribed by the Federal Trade Commission for testing materials of this kind, indicated the absorbing power of the material prepared from citrus waste in accordance with the method described herein.

The granulated material: a cigarette holder with a piston loosely filled with the granulated material was used. On the basis of tests, an average cigarette, 75% of the tar and 62% of the nicotine were absorbed. The measurements on the cigarettes indicated that a single cigarette contained 16 milligrams of tar and 0.75 milligram of nicotine.

Using filter paper in a similar test, the figures showing absorption by the filter butt from one cigarette on a statistical sampling of a large number of cigarettes showed 68% of the tar and 58% of the nicotine absorbed.

It is, of course, apparent that the degree of absorption of tar or nicotine can only approach the theoretical limit of 100%. The effectiveness of the particular material must 4;. always be measured in terms of the /2 inch to /1 inch filter tip space available on an individual cigarette.

Since the active absorbing agent for the tobacco tar and nicotine is the citrus pulp, its form and amount is directly related to the efficiency of the absorption. When the filter consists of macerated pulp powder itself, it is most effective, because all the surfaces in the filter are citrus pulp. Thus, the filter can be made to be pulp. For convenience in manufacturing the paper sheet carrying pulp is quite handy and, for this purpose, it is impregnated with the pulp. Generally, amounts of 50-75% are readily included in the paper, giving it a texture of a chemical filter paper and a somewhat mottled appearance as a result of having the random distribution of the pulp therein. Here again, since the surface area for absorption is related to the amount of pulp, the 50-75% represents an intermediate amount in that is gives a strong paper with much surface area for absorption. Amounts as low as 25% citrus pulp in the paper can be used, but only with proportionate loss of filtering or tar absorbing efiectiveness.

What is claimed is:

1. A tobacco smoke filter comprising a cylindrical container defining a space having an inlet and an outlet and through which tobacco smoke is made to pass, a smokepermeable plug at the inlet and outlet ends of said container, the space between said plugs being filled with a partially hydrolyzed, dried, granulated citrus fruit pulp freed of pectin and proteinaceous matter.

2. A tobacco smoke filter comprising a cylindrical container defining a space having an inlet and an outlet and through which tobacco smoke is made to pass from one end through to the other, said space being filled with coiled cellulosic paper impregnated with a partially hydrolyzed, dried, granulated citrus fruit pulp freed of pectin and proteinaceous matter.

3. A tobacco smoke filter comprising a cylindrical container defining a space, an inlet and an outlet in said container through which tobacco smoke is made to pass, said space containing as a smoke permeable filtering material, partially hydrolyzed, dried, granulated citrus fruit pulp, freed of pectin and proteinaceous matter.

References Cited UNITED STATES PATENTS 1,310,404 7/1919 Irving 131261 X 1,528,469 3/1925 Davidson 99133 X 1,776,362 9/1930 Loesch 99133 X 1,838,949 12/1931 Taylor et al 99133 2,097,081 10/ 1937 Rooker 99--133 2,768,913 10/1956 Hiler 131-109 2,801,178 7/1957 Leo et al 99133 X 3,034,931 5/1962 Kiefer 1312 3,234,948 2/1966 Stebbings 131265 X 3,319,630 5/1967 Orrmins 131-10.7 3,330,285 7/1967 Bergquist 131--10.7

SAMUEL KOREN, Primary Examiner.

D. J. DONOHUE, Assistant Examiner. 

